The common theme of the projects is the assessment of differentiation of electrical properties in different tissues in a variety of animals, and in different stages of development of the same animal. We divide the research plan into three categories. ANALYSIS OF CA CHANNEL. The permeability of the Ca channel will be examined by altering ions inside the cell. Questions are: i) Can divalent cations carry outward currents?, ii) How internal monovalent cations affect the reversal potential?, iii) Do divalent cations inside block the outward monovalent cation current as they do externally? It has been shown that different types of Ca channels exist. Are there any phylogenetical principles? We would like to study Ca channels in plant cells, the trap-lobe of Venus flytrap using protoplasts, which have no cell wall. We would also like to examine the expression of Ca channel by extracting mRNA of clonal lymphocyte cells which have Ca currents. STUDIES ON NEURONS IN MAMMALIAN CENTRAL NERVOUS SYSTEM. We would like to initiate this project with primary culture of rat cerebellar cortex. Ion channels, particularly non-inactivating Na channels and Ca channels, will be studied in Purkinje cells. Glutamate-aspartate type excitatory postsynaptic receptors will be classified in Purkinje cells. Properties of the granule-Purkinje cell synapse will be analysed. We would like to make co-cultures of Purkinje and granule cells with inferior olive cells to examine the interaction between these two types of excitatory inputs to the Purkinje cell. ELECTROPHYSIOLOGICAL APPROACHES TO IMMUNOLOGICAL PHENOMENA. Hybridomas secreting immunoglobulin (lg) have Ca channels. The significance of the Ca channel and its role in lg secretion is one aim of these studies. The other project is to study the ionic properties of the membrane during the maturation of human B lymphocyte, from small resting B lymphocytes into large non-proliferating blast cells, proliferating non-lg secreting blast and finally mature lg- secreting cells. Each of these cellular stages can be isolated by using appropriate lymphokines or reagents.